Update rest-dbus

Removed upstreamed patches to makefile.
Updated path in systemd service file.
Add dependency on mapper.
diff --git a/common/recipes-phosphor/rest-dbus/files/rest-dbus.service b/common/recipes-phosphor/rest-dbus/files/rest-dbus.service
index 686cf69..b6f9b97 100644
--- a/common/recipes-phosphor/rest-dbus/files/rest-dbus.service
+++ b/common/recipes-phosphor/rest-dbus/files/rest-dbus.service
@@ -2,7 +2,7 @@
 Description=DBUS introspecting REST server.
 
 [Service]
-ExecStart=/usr/bin/rest-dbus
+ExecStart=/usr/sbin/rest-dbus
 
 [Install]
 WantedBy=multi-user.target